The method of the construction of the Roman roads largely varied with the nature of the country traversed; but they were uniformly raised above the surface of the neighbouring land, and ran from station to station in a straight course, almost regardless of hills. The more important lines were elaborately constructed with a foundation of hard earth, a bed of large stones, sometimes two more layers of rough stones and mortar, then gravel, lime, and clay; and, above all, the causeway was paved with flat stones. The width was generally about fifteen feet, and at regular intervals were posting stations. The distance was regularly marked off by milestones (mille passuum—a thousand paces). The principal roads were four in number, viz., Watling Street, the Fosse Way, Icknield Street, and Ermine Street.
Originally, Watling Street probably ran from London to Wroxeter. Its northward and westward continuations proceeded from Wroxeter into Wales; its southern continuations between London, Canterbury and the parts about Dover seem also to have received the same name.
Drayton, in his Polyolbion, XIII (1613), says:
| "Those two mighty ways, the Watling and the Fosse ... the first doth hold her way From Dover to the furth'st of fruitful Anglesey; The second, north and south, from Michael's utmost mount, To Caithness, which the farth'st of Scotland we account." |
The Fosse ran from the sea-coast at Seaton, in Devonshire, (R. Maridunum) to Leicester, with a continuation known as High Street, to the Humber.
The Icknield Way seems to have extended from east to west from Icilgham, or Icklingham, near Bury St. Edmunds, underneath the chalk ridge of the Chilterns and Berkshire Downs, to the neighbourhood of Wantage, thence to Cirencester and Gloucester.
The Ermine Street ran north and south through the Fenland from London to Lincoln.
Besides the four great lines there were many scarcely subordinate ones. There were, e.g., several Icknield Streets. Akeman Street ran from Bath, north-east by Cirencester, through Wych-wood Forest and Blenheim to Alcester and Watling Street. A high-road ran from Exeter to the Land's End in continuation of the Fosse. Another route ran from Venta Silurum to St. David's Head; another to the Sarn Helen up the western Welsh coast to Carnarvon (Welsh, sarn—a road).